Sang-Yun Lee

The results of cardiopulmonary exercise test in healthy Korean children and adolescents: single center study.

Purpose The cardiopulmonary exercise test (CPET) is an important clinical tool for evaluating exercise capacity and is frequently used to evaluate chronic conditions including congenital heart disease. However, data on the normal CPET values for Korean children and adolescents are lacking. The aim of this study was to provide reference data for CPET variables in children and adolescents. Methods From August 2006 to April 2009, 76 healthy children and adolescents underwent the CPET performed using the modified Bruce protocol. Here, we performed a medical record review to obtain data regarding patient demographics, medical history, and clinical status. Results The peak oxygen uptake (VO2Peak) and metabolic equivalent (METMax) were higher in boys than girls. The respiratory minute volume (VE)/CO2 production (VCO2) slope did not significantly differ between boys and girls. The cardiopulmonary exercise test data did not significantly differ between the boys and girls in younger age group (age, 10 to 14 years). However, in older age group (age, 15 to 19 years), the boys had higher VO2Peak and METMax values and lower VE/VCO2 values than the girls. Conclusion This study provides reference data for CPET variables in case of children and adolescents and will make it easier to use the CPET for clinical decision-making.

The echocardiographic paradox index in patients with a repaired tetralogy of Fallot

Abstract Objectives. Right ventricular (RV) volume is very important for pulmonary valve replacement after the total correction of tetralogy of Fallot (TOF), and we attempted to identify a convenient echocardiographic index that is well correlated with the volumetric data obtained through magnetic resonance imaging (MRI). Design. All patients who underwent cardiac MRI and echocardiography at Sejong General Hospital for evaluating pulmonary regurgitation after TOF total correction were included. The paradox index is the amount of paradoxical motion of the interventricular septum on the short-axis echocardiographic view. The paradox index was compared to several cardiac MRI indices. Results. Fifty-four patients were included. The paradox index for all patients was 1.22 ± 0.12 (1.06–1.67), and the index of the operation group was significantly higher than that of the non-operation group (1.26 ± 1.12 vs1.16 ± 1.12, P = 0.009). The paradox index was well correlated with the RV systolic and diastolic volumes, as measured by cardiac MRI (P = 0.002 and 0.003). Using a simple linear regression analysis, a paradox index of 1.24 corresponded to a RV diastolic volume of 160 ml/m2. Conclusions. The paradox index could help to indicate the time for an MRI analysis of the RV volume in patients after TOF total correction.

Outcomes of Aortopexy for Patients With Congenital Heart Disease

Aortopexy is a surgical procedure in which the aortic arch is fixed at other structures, thus widening the interaortic space. This study aimed to evaluate the outcome of aortopexy by means of chest computed tomography for patients with congenital heart disease. The study retrospectively reviewed the medical records of 16 patients with congenital heart disease who had undergone aortopexy by compressed airway. The severity of compressed bronchus before aortopexy, immediately after aortopexy (≤1xa0month), and after the patient had grown up were compared. To estimate the efficacy of the aortopexy, the interaortic distance index was calculated. Of the 16 patients, aortopexy was performed at the ascending aorta in 7, at the descending aorta in 7, and at the transverse arch in 2. The diameter ratio between the narrowest bronchus and the trachea was improved after aortopexy, as was the diameter ratio before aortopexy versus immediately after aortopexy (nxa0=xa09; pxa0=xa00.018) and the diameter ratio before aortopexy versus after the patient had grown up (nxa0=xa011; pxa0=xa00.006). Also, the interaortic distance index was increased after aortopexy, as was the diameter before aortopexy versus immediately after aortopexy (nxa0=xa09; pxa0=xa00.039) and the diameter before aortopexy versus after the patient had grown up (nxa0=xa011; pxa0=xa00.014). The study had one case of mortality due to sepsis. As shown by the results, aortopexy in patients with a compressed airway between arches is a useful surgical option. Such a compressed airway between arches should be considered for patients with an unusual clinical course before and after open heart surgery.

Transcatheter Closure of Secundum Atrial Septal Defect in Patients Over 60 Years Old

Background and Objectives Atrial septal defect (ASD) is the one of most common congenital heart diseases detected in adults. Along with remarkable development of device technology, the first treatment strategy of secundum ASD has been transcatheter closure in feasible cases. However, there are only a few publications regarding the results of transcatheter closure of ASD in elderly patients, especially those over 60 years of age. We report our results of transcatheter closure of ASD in patients over 60 years old. Subjects and Methods Between May 2006 and December 2011, 31 patients over 60 years old (25 female and 6 male; mean 66.7±5.25 years old, range 61-78 years old) were referred to our center. Results A total of 23 patients underwent therapeutic catheterization to close secundum ASD, and the closure was successful in 22 patients (95.7%). All patients who underwent the procedure survived except for one patient who expired because of left ventricular dysfunction. A small residual shunt was observed in two (9%) of 21 patients before discharge but disappeared at follow-up. All patients eventually had complete closure. There were five patients who had coronary problems. One patient underwent percutaneous coronary intervention using a stent at the same time as transcatheter closure of ASD. Atrial arrhythmias were detected in 6 of 23 patients (26.1%) before the procedure. One patient was successfully treated by radiofrequency ablation before the procedure. No patients displayed new onset arrhythmia during the follow-up period. Follow-up echocardiographic evaluation showed a significantly improved right ventricular geometry. Conclusion We conclude that transcatheter closure of ASD is a safe and an effective treatment method for patients over 60 years old if the procedure is performed under a thorough evaluation of comorbidities and risk factors.

Palliation Using a Self-expandable Stent in a Patient with Obstructive Right-Ventricular Outflow Tract after Total Correction of Tetralogy of Fallot

Total correction of tetralogy of Fallot (TOF) is typically performed within the first year of life. However, subsequently, right-ventricular dysfunction often progresses by pulmonary stenosis or regurgitation. Although most patients with corrected TOF require additional surgery for right-ventricular outflow tract, intervention could be an alternative to palliative surgery and associated morbidities, especially in children. We describe a palliative application of the self-expandable stent in a patient with pulmonary stenosis after total correction of TOF who lacked a conduit between the right ventricle and pulmonary artery.

Hemodynamic Follow-Up in Adult Patients with Pulmonary Hypertension Associated with Atrial Septal Defect after Partial Closure

Purpose We evaluated the hemodynamic statuses of patients after partial closure of atrial septal defects with fenestration due to pulmonary hypertension. Materials and Methods Seventeen adult patients underwent partial atrial septal defect closure and follow-up cardiac catheterization. We analyzed hemodynamic data and clinical parameters before and after closure. Results The median age at closure was 29 years old. The baseline Qp/Qs was 1.9±0.6. The median interval from the operation to the cardiac catheterization was 27 months. The CT ratio decreased from 0.55±0.07 to 0.48±0.06 (p<0.05). The mean pulmonary arterial pressure decreased from 50.0±11.5 mm Hg to 32.5±14.4 mm Hg (p<0.05), and the pulmonary resistance index decreased from 9.2±3.6 Wood units*m2 to 6.3±3.8 Wood units*m2 (p<0.05). Eleven patients (64.7%) continued to exhibit high pulmonary resistance (over 3.0 Wood units*m2) after closure. These patients had significantly higher pulmonary resistance indices and mean pulmonary arterial pressures based on oxygen testing before the partial closures (p<0.05). However, no significant predictors of post-closure pulmonary hypertension were identified. Conclusion Despite improvement in symptoms and hemodynamics after partial closure of an atrial septal defect, pulmonary hypertension should be monitored carefully.

Hepatic Stiffness Using Shear Wave Elastography and the Related Factors for a Fontan Circulation

Hepatic problems related to a Fontan circulation have been highlighted and elastography using ultrasound is a non-invasive tool that can measure the severity of hepatic stiffness. We investigated the hepatic stiffness using shear wave elastography (SWE) and related factors in patients with a Fontan circulation. This study enrolled 64 patients with a Fontan circulation who underwent cardiac catheterization and abdominal ultrasound from 2011 to 2015. The correlation between the laboratory tests, hemodynamic factors by cardiac catheterization, and SWE was evaluated. The patients were classified into non-cirrhotic level (≥xa02.0xa0m/s) and cirrhotic level (<xa02.0xa0m/s) groups by the SWE value. The mean age was 17.6xa0years and the mean duration after the Fontan operation was 12.1xa0years. The mean value of SWE in patients (1.95xa0m/s) was higher than the normal (<xa01.3xa0m/s). The SWE was higher in patients without than those with a fenestration (2.03 vs. 1.75xa0m/s, Pxa0=xa00.003). In a multiple regression analysis between SWE and other factors, the CVP, fenestration, and lipoprotein Apo B had a significant correlation. In a multivariate analysis of cirrhotic level group, the CVP was the only significant factor. The hepatic stiffness had significantly progressed in most patients with a Fontan circulation. A low CVP and Fontan circulation with a fenestration might reduce the progression of the hepatic stiffness.

Impact of postoperative duration of Aspirin use on longevity of bioprosthetic pulmonary valve in patients who underwent congenital heart disease repair

Purpose Generally, aspirin is used as a protective agent against thrombogenic phenomenon after pulmonary valve replacement (PVR) using a bioprosthetic valve. However, the appropriate duration of aspirin use is unclear. We analyzed the impact of postoperative duration of aspirin use on the longevity of bioprosthetic pulmonary valves in patients who underwent repair for congenital heart diseases. Methods We retrospectively reviewed the clinical data of 137 patients who underwent PVR using a bioprosthetic valve between January 2000 and December 2003. Among these patients, 89 were included in our study and divided into groups I (≤12 months) and II (>12 months) according to duration of aspirin use. We analyzed echocardiographic data from 9 to 11 years after PVR. Pulmonary vale stenosis and regurgitation were classified as mild, moderate, or severe. Results The 89 patients consisted of 53 males and 36 females. Their mean age was 14.3±8.9 years (range, 2.6–48 years) and body weight was 37.6±14.7 kg (range, 14–72 kg). The postoperative duration of aspirin use was 7.3±2.9 months in group I and 32.8±28.4 months in group II. However, no significant difference in sex ratio, age, body weight, type of bioprosthetic valve, and number of early redo-PVRs. In the comparison of echocardiographic data about 10 years later, no significant difference in pulmonary valve function was found. The overall freedom rate from redo-PVR at 10 years showed no significant difference (P=0.498). Conclusion Our results indicated no benefit from long-term aspirin medication (>6 months) in patients who underwent PVR with a bioprosthetic valve.

Stepwise Approach Using Combined Management in Patients with Congenital Heart Disease and Borderline Pulmonary Vascular Disease.

Background and Objectives Despite remarkable advances in pediatric cardiology, pulmonary arterial hypertension associated with congenital heart disease remains a major problem. In the past decade new vasodilators have been introduced and appear to be effective in reducing pulmonary vascular resistance (PVR). Subjects and Methods From 2000 to 2011, we retrospectively reviewed the records of 22 patients who had congenital septal defects and borderline pulmonary vascular disease (PVD). The PVR in these patients was from 6 to 16 wood units · m2, and/or the systolic pulmonary arterial pressure was more than 2/3 of the systemic arterial pressure. Results The median age was 16 years (range, 9 months-46 years). The median duration of follow-up was 7.4 years (range, 1.4-11.7 years). According to hemodynamic data and clinical symptoms, the initial management comprised targeted medical therapy in four (18%), complete closure in four (18%), and partial closure in 14 patients (63.6%). In the four patients who had a high PVR and negative vasoreactivity, the PVR decreased and vasoreactivity increased after targeted medical therapy; three of these patients underwent cardiac surgery later. Finally, 11 (50%) received targeted medical therapy and 21 patients (95.4%) underwent cardiac surgery. Complete closure resulted in six patients and partial closure in 17 patients. Mortality was observed in two patients. The other 19 patients (91%) had New York Heart Association functional class I. Conclusion Targeted medical therapy may be effective in reducing PVR in patients with congenital heart disease and borderline PVD. A stepwise approach may help to achieve improved outcomes in these patients.